# 加法
# sum = 1 + 2
# sum2 = 1.0 + 2.0
# print (sum, "/", sum2)
# # 3 / 3.0

# sub = str(1) + "a"
# print (sub)

# print (3 / 2)
# # 1.5
# print (3.0 / 2)
# # 1.5
# print (3 / 2.0)
# # 1.5
# print (3.0 / 2.0)
# # 1.5
# print (3.0 / int('2'))
# # 1.5

# print(3-2)
# # 1
# print(3.0-2)
# # 1.0
# print (3 - 2.0)
# # 1.0

# print (1 * 2)
# print (1. * 2)
# print (1 * 2.)
# print (1. * 2.)
# # 2
# # 2.0
# # 2.0
# # 2.0

# print (13 // 3)
# print (13. // 3)
# # 4
# # 4.0

# print (13 % 4)
# print (13 % 4.)
# print (13.3 % 4)
# # 1
# # 1.0
# # 1.3000000000000007

# print (4 ** 2)
# # 16

